49
Instructional Leaflet
IB2C12063H03
Effective March 2012
Instructions for Installation, Operation and
Maintenance of Magnum SB Insulated Case
Low Voltage Power Circuit Breakers
EATON CORPORATION
www.eaton.com
Spring Release
The spring release is an optional device (
Figure 63
) . It remotely
closes the circuit breaker when the coil is energized by a
voltage input (
Table 8
) . The closing spring must be fully charged
and the trip latch reset (not held in the tripped position) for the
SR to operate . If these two conditions are not met the close
signal will be ignored until it is removed and re-applied .
An optional Latch Check Switch (LCS) can be installed to
indicate when the circuit breaker is ready to close . Two versions
of the LCS are available .
The Latch Check Switch wired to the Spring Release will not
permit activation of the Spring Release until the circuit breaker
is fully charged and the trip latch is reset (
Figure 63
) . If power
is applied and maintained to the Spring Release, an activation
will occur when the circuit breaker is “ready to close” .
The Latch Check Switch for Remote Indication consists of 1
Form C contact wired to the circuit breaker secondary contacts
for integration into external control schemes . Note that wiring
the LCS for Remote Indication directly in series with the SR
accessory is not recommended as this will override the “anti-
pump” feature of the electrical charging/closing system .
Figure 63. Spring Release with Optional Latch Switch
Table 8. Spring Release Ratings
Control
Voltages
Operational
Voltage Range
70-110%
Inrush Power
j
Consumption
Closing
Time (ms)
24 Vdc
17-26 Vdc
250 W
40
48 Vdc
34-53 Vdc
250 W
40
110-125 Vdc
77-138 Vdc
450 W
40
220-250 Vdc
154-275 Vdc
450 W
40
110-127 Vac
77-140 Vac
450 VA
40
208-240 Vac
146-264 Vac
450 VA
40
j
Required for less than 200 ms
Undervoltage Release
The undervoltage release is an optional device on both
manually and electrically operated circuit breakers (
Figure
64
) . It opens the circuit breaker when its supply voltage falls
to between 35-60% of rated voltage . If the release is not
energized to 85% of its supply voltage, the circuit breaker
cannot be closed electrically or manually (
Table 10
) .
Auxiliary Switch
An auxiliary switch is an optional device providing remote
electrical indication if the circuit breaker is open or closed
(
Figure 66
) . Up to 3 auxiliary switches can be mounted in the
circuit breaker . Each switch has 2 normally open (“a”) and
2 normally closed (“b”) contacts for a total of 12 available
contacts (
Table 9
) .
Figure 64. Undervoltage Release
Figure 65. Shunt Trip, Spring Release and Undervoltage Release
Installed